Hello all, where does the stock HPFP and LPFP max out with the direct injectors on pump gas 93? I do not have E85 where I am located, so I am trying to figure out if a single turbo is worth it. My power goal is around 500WHP. I'd like to know if this is attainable on 93 without any fueling mods. I suppose I'd have to run a bigger turbo that if I had E85, as I'd need all the flow I can get for the "low" octane of 93. Additionally, will I still be able to daily it at this power level?
Stock fueling limits?
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Given wanting to stay on 93oct with no port-injection nor water/meth, a tuner will usually see an N54 at its best comfort level between a 17-19psi boost target and <7* of timing on a single-turbo setup.
It's up to you whether you run a turbo sized anywhere from a 62 to a 68mm compressor, results will be fairly similar at the given rate. That's as long as your HPFP, LPFP, and Injectors are in good shape. Not to mention, it's very important to run a "Stage 2" LPFP setup at minimum on an upgraded turbo setup, which is a 450lph pump or better. I personally run a bucket-less Walbro 535lph LPFP.
Given the setup's octane, boost, and timing, it's fairly common to see anywhere from 490-520whp, depending on overall engine health, outside temps, and similar conditions that all play a role into how performance on the dyno will be.
People will daily-drive built N54's with port-injection, twin LPFP's, upgraded twin / single turbo, and all the other goodies with no issue. With your goal, that's a mosquito bite on the N54's longevity. You have plenty of room left as long as you maintain it accordingly with how you plan to treat it.
It's up to you whether you run a turbo sized anywhere from a 62 to a 68mm compressor, results will be fairly similar at the given rate. That's as long as your HPFP, LPFP, and Injectors are in good shape. Not to mention, it's very important to run a "Stage 2" LPFP setup at minimum on an upgraded turbo setup, which is a 450lph pump or better. I personally run a bucket-less Walbro 535lph LPFP.
Given the setup's octane, boost, and timing, it's fairly common to see anywhere from 490-520whp, depending on overall engine health, outside temps, and similar conditions that all play a role into how performance on the dyno will be.
People will daily-drive built N54's with port-injection, twin LPFP's, upgraded twin / single turbo, and all the other goodies with no issue. With your goal, that's a mosquito bite on the N54's longevity. You have plenty of room left as long as you maintain it accordingly with how you plan to treat it.
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Thank you for the response, can I ask what power level I would be at without touching the LPFP?
It's hit or miss. Some people will see their LPFP start to show signs of weakness or failure on as little as MHD's "Stage 1+" (<380whp) off-the-shelf tune. Others can go as far as their "Stage 2+" (<420whp) tune or slightly higher, (custom tune,) before seeing signs of weakness or failure.
Not to mention running an ethanol blend, even MHD recommends that you upgrade your LPFP before selecting an ethanol blend option for one of their off-the-shelf tunes. By the point of a custom tune involving an ethanol blend (<420whp+,) it's a high priority to upgrade your LPFP.
Not to mention running an ethanol blend, even MHD recommends that you upgrade your LPFP before selecting an ethanol blend option for one of their off-the-shelf tunes. By the point of a custom tune involving an ethanol blend (<420whp+,) it's a high priority to upgrade your LPFP.
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